. >> if you are an undocumented worker in america, you are a captive. >>female farm workers empowered to speak out. >> frontline correspondent lowell bergman, in collaboration with univision and the center for investigative reporting, investigate. >> no one's ever been charged for rape or assault? >> no. >> tonight, "rape in the fields." frontline is made possible by contributions to your pbs station from viewers like you. and by the corporation for public broadcasting. major support for frontline is provided by the john d. and catherine t. macarthur foundation, committed to building a more just, verdant and peaceful world. more information is available at macfound.org. additional funding is provided by the park foundation, dedicated to heightening public awareness of critical issues. and by the frontline journalism fund, with grants from jon and jo ann hagler on behalf of the jon l. hagler foundation. and scott nathan and laura debonis. >> lowell bergman: there are over a half-million women working in the fields of america. most are undocumented immigr